Automatic panning system

ABSTRACT

An automatic panning system and method adapted for a vehicle with an attached trailer. The automatic panning system comprises an image capturing means adapted to capture image data with a view of the trailer and the automatic panning system is adapted to analyze the image data to identify at least one elongated element of the trailer, project a vector in the image data based on said elongated element, establish at least one reference vector, and identify an interception point of the reference vector and said projected vector.

TECHNICAL FIELD

The present invention relates generally to a panning system for panninga rear view image in a vehicle.

BACKGROUND ART

In prior art it is known to provide solutions for enhancing the rearview visibility for a vehicle driver. Solutions are known for differentvehicles, one example is a truck with a trailer. Conventional rear viewmirrors and side mirrors wherein the reflection is used to present arear view has been used in the art for a long time and for examplefeatures that the mirrors can be manually adjusted by the driver. Inaddition to adjusting the mirror the driver has the possibility to movethe perspective of the mirror through moving around in relation to themirror. This is often done through the driver moving his head andresults in that different portions of the area behind the vehicle becomevisible.

Arranging one or more cameras, either as a complement or to replace theconventional rear view mirrors, is well known. The cameras are adaptedto show a rear view in relation to the vehicle and such solutions has inthe art previously been utilized both for rear view cameras andelectronic rear view mirrors.

For electronic rear view mirrors and reverse cameras the prior artfurther presents systems enabling that the image is panned. Panningmeans that the camera or image can be adjusted to show differentportions of the section behind the vehicle in a similar way as the userachieves through moving his head in relation to a mirror in theconventional rear view mirror systems. However, the systems of the priorart comprises multiple drawbacks, especially for vehicles that tow atrailer. When a vehicle with an attached trailer turns the trailer willobstruct the view of the rear view mirror making it difficult for thedriver to see how the trailer moves. This is a problem present both intraditional mirror systems and in prior art rear view systems utilizingcameras.

SUMMARY OF INVENTION

As discussed it is a problem with rear view mirrors, side view mirrors,and rear view cameras based on image capturing from a device, such as acamera, that the user's perspective angle in relation to the mirrordon't affect the image displayed from the camera. In a traditionalreflective mirror the driver can move his head to control the field ofview. In a display system this is not possible since the angle of theusers head won't affect the display angle. To achieve the same field ofview the displayed image either needs to constantly display much more ofthe surrounding area than a traditional mirror or it needs to be panned.Solutions displaying more information can be beneficial in someembodiments but at the same time results in resolutions of the imagethat makes it difficult for the operator to distinguish smaller objects.

Panning systems are therefore a good alternative and there are many waysof performing panning. One solutions is to use object recognition in animage recorded by an image capturing device, store the position of aspecific object in the image data and pan the image through making surethat the identified object always is in the same relative position inthe panned image data displayed to the user.

The panning can be achieved either through physically moving the angleof the image capturing means or having an image capturing meansconstantly capturing image data of a larger area than displayed to theuser. The latter instead crops the image data into the correct sectionin order to display the most useful information.

The operation of panning an image presents multiple problems in relationto how the panning operation is performed. In order to provide a gooduser experience and replace traditional mirrors it is important that theimage data is panned in a natural way with a consistent result. Oneoption as present in prior art is that the user manually can control thepanning in a way similar to adjusting a traditional rear view mirror.This adds an additional task to maneuvering of the vehicle resulting ina solution that is difficult and inconvenient for the user to use.

Automatic panning can be conducted in different ways as realized by theinventors. However, most solutions evaluated by the inventor suffer fromdrawbacks that are similar to the manual panning. For example, it ispossible to conduct panning through recognizing a specific feature of atowed object, such as a trailer, in an image. The recognized object canbe a logo, indicator, or any other form of object that is identifiablein an image somewhere at the towed object. Through analyzing the imagescaptured during operation the relative position of the recognized objectin the image can be identified. Based on the relative position of anobject the panning operation can thereby be controlled through panningthe image maintaining the recognized object in the same relativeposition at all times. This solution solves some of the problems of theprior art but has multiple drawbacks especially in relation to how theimage panning works. The image panning isn't dependent on a pointlocated at any specific location of the trailer and can with differenttowing objects be placed at different places along the length and heightof the towing object. This provides a solution wherein the rotating axisof the panning might not correspond to how the towing object actuallymoves and thereby provide an unnatural and distorted panning experiencefor the user. Furthermore, such solutions can present different resultsat different times causing confusion for the vehicle operator.

There are additional drawbacks with solutions depending on locatingobjects in an image relating to required processing power. Conductingsuch operations in real-time requires large calculation capacity fromthe device conducting the operation and there is a risk for delays inthe system.

It is thereby one object of the present solution to provide a naturaland undistorted panning operation that presents consistent results tothe user.

Another object of the present solution is to provide a solutionrequiring less computer power.

Another object of the present solution is to provide side view mirrorsenabling a better overview for the user than conventional side viewmirrors.

Another object of the present solution is to display useful informationto the driver without compromising attention to traffic.

Thus, the solution relates to an automatic panning system adapted for avehicle with an attached trailer, wherein said automatic panning systemcomprises an image capturing means adapted to capture image data with aview of the trailer. The automatic panning system is adapted to analyzethe image data to identify at least one elongated element of thetrailer, project a vector in the image data based on said elongatedelement, establish at least one reference vector, and identify aninterception point of the reference vector and said projected vector.

The automatic panning system herein relates to panning for image datacorresponding to data from side view mirrors (also in the art calledfender mirrors, door mirrors, or wing mirrors), but could as understoodby the person skilled in the art also be implemented in a rear viewmirror or in relation to a rear view camera.

Through identifying an elongated element, such as the lower edge of thetrailer or an elongated part of a print on the trailer, it is possibleto conduct calculations without constantly analyzing the images in thesame way as required when conducting panning with a system as previouslydescribed. The elongated element is used to project a vector that can becompared with the established reference vector resulting in aninterception point. This is advantageous both since the interceptionpoint provides a consistent point in relation to the length of thetrailer to pan the image data from but also from that the calculationsaims to find an interception between the projected vector and areference vector instead of constantly analyzing an object.

The interception point corresponds to a point in the close vicinity ofan end point of the trailer making the panning operation consistent andaccurate independent of the size, shape, form, and characteristics oftrailer that is attached to the vehicle.

As previously described it is a problem with prior art solutions thatautomatic panning functions differently depending on where the rotationaxis for the trailer is located in relation to the point the panningsystem uses to pan the image. Through calculating the position of therear end of the trailer instead of identifying merely an object based onobject recognition it is possible to solve this problem, as will befurther described herein.

According to one embodiment the projected vector can be projected at aconstant offset along the identified elongated element.

According to one embodiment the projected vector is a tangent of theelongated element.

According to one embodiment the panning speed is adjusted to provide asmoother experience.

A smother panning can be achieved through adjusting the speed thepanning is performed at, this has the effect that a more naturalexperience is achieved.

According to one embodiment of the automatic panning system adapted fora vehicle with an attached trailer, wherein said automatic panningsystem comprises an image capturing means adapted to capture image datawith a view of the trailer. The automatic panning system is adapted toanalyze the image data to identify at least one elongated element of thetrailer, project a vector in the image data based on said elongatedelement, establish at least one horizontal reference, and identify aninterception point of the horizontal reference and said projectedvector.

It is one advantage with the present solution that a horizontalreference in the form of a reference vector can be established in theimage data. The horizontal reference is in one embodiment based oninformation available in the background, such as the horizon or anyother substantially flat object that can be identified and used toproject a reference vector.

According to one embodiment the automatic panning system is furtheradapted to establish the horizontal reference such that said identifiedinterception point corresponds to the position of the rear end of thetrailer in the captured image data.

It is one advantage with the present solution that the rear end of thetrailer can be identified through the interception point between thevectors. This solution enables an enhanced automatic panning.

According to one embodiment the automatic panning system further isadapted to pan the captured image data based on the identifiedinterception point.

According to one embodiment the automatic panning system further isadapted to, in real time, present the panned captured image data to anoperator of the vehicle.

According to one embodiment the identified elongated element is selectedfrom any one of the longitudinal lower edge of the trailer, thelongitudinal top edge of the trailer, the vertical rear edge of thetrailer, and a printed element on the trailer side.

According to one embodiment the reference vector is determined based onat least one distinct point in the background of the captured imagedata.

The reference vector is in one embodiment calculated based on edgedetection in the background of the image data.

According to one embodiment a continuous panning that isn't shown to theuser of the vehicle is performed creating, from fixed objects in thebackground, as well as the horizon, information about objects that don'tchange in a vertical direction. Based on such objects the referencevector is established to create a panning that don't change in thevertical direction.

According to one embodiment the reference vector is a horizontalreference vector.

According to one embodiment the automatic panning system furthercomprises a display, a memory, and a processor unit.

According to one embodiment the image capturing means is arranged on topof the vehicle towing the trailer.

According to one embodiment the image capturing means is arranged at aheight corresponding to at least 80% of the trailer height.

According to one embodiment the image capturing means is arranged at thesame spot as a rear view mirror normally is arranged.

According to one embodiment the image capturing means is arrangedtogether with a side mirror.

According to one embodiment the image capturing means is arrangedinstead of a side mirror.

According to one embodiment the image capturing means is arranged at thesame spot as a side mirror normally is arranged.

According to one embodiment the system is further adapted identify afurther interception point on the opposite side of the trailer from theinterception point, establish if the further interception point is in aposition that based on at least one of the physical properties of thetrailer, the previous position of the trailer, and the interceptionpoint is possible.

It is one advantage that through utilizing the embodiment whereininterception points are identified on both sides of the trailer throughanalyzing image data. The image data is analyzed to identify at leastone elongated element of the trailer on each side. On each side a vectoris projected in the image data for based on the elongated element. Thesystem is further adapted to establish at least one reference vector foreach side and identify an interception point where the reference vectorsand projected vectors for each side cross. This can be used to determineif there is any unexpected or unreasonable readings in relation to thetrailer movement through analyzing how the interception points move,i.e. if the interception point is possible or not. Thereby the solutioncan be used to decrease the number of errors making the panning moreaccurate.

According to one embodiment the further interception point is used toremove error results.

According to one embodiment information about the trailer position iscalculated from at least one interception point.

According to one embodiment the trailer position is recorded to a memoryenabling that the automatic panning system knows the latest position ofthe trailer.

It is one advantage with the present solution that the automatic panningsystem knows the latest position of the trailer. In one embodiment thelatest position of the trailer is used when the system is rebooted, forexample when the vehicle is started, as an initial position of thetrailer.

According to one embodiment the automatic panning system is adapted toanalyze, based on at least one interception point, if the trailer ismoving in a natural and/or predictable way.

It is one advantage that results that are not relevant or error resultscan be filtered from the solution creating a better panning experience.

According to one embodiment the automatic panning system further isadapted to calculate the vehicle speed as a function of the velocity andangle of the wheels to predict a trailer movement.

According to one embodiment, the automatic panning system is adapted toanalyze the image data to estimate the trailer's angle using the imagecapturing means and predict the trailer's rotational derivative, inparticular the derivative of the trailer's angle, using derivatecalculation parameters comprising at least one of the length of thetrailer, the trailer's hitching offset, the distance between thevehicles wheel axles, the vehicle's speed, and the steering wheel angleof the vehicle, and in that the automatic panning system further isadapted to use the trailer's angle and the calculated derivative topredict a future trailer angle.

According to one embodiment, the automatic panning system is adapted toanalyze the image data to estimate the trailer's angle using the imagecapturing means and predict the trailer's rotational derivative, inparticular the derivative of the trailer's angle, using derivativecalculation parameters comprising the distance between the wheels of thetrailer, the distance between the wheels and the hitching point, thesteering angle of the front wheels and/or the steering wheel angle, andthe speed of the vehicle, and in that the automatic panning systemfurther is adapted to use the trailer's angle and the calculatedderivative to predict a future trailer angle.

According to one embodiment an automatic panning system adapted for avehicle with an attached trailer is provided, wherein said automaticpanning system comprises an image capturing means adapted to captureimage data with a view of the trailer, characterized in that theautomatic panning system is adapted to analyze the image data toestimate the trailer's angle using the image capturing means and predictthe trailer's rotational derivative, in particular the derivative of thetrailer's angle, using derivative calculation parameters comprising atleast one of the length of the trailer, the trailer's hitching offset,the distance between the vehicles wheel axles, the vehicle's speed, andthe steering wheel angle of the vehicle, and in that the automaticpanning system further is adapted to use the trailer's angle and thecalculated derivative to predict a future trailer angle.

According to one embodiment, an automatic panning system adapted for avehicle with an attached trailer is provided, wherein said automaticpanning system comprises an image capturing means adapted to captureimage data with a view of the trailer, characterized in that theautomatic panning system is adapted to analyze the image data toestimate the trailer's angle using the image capturing means and predictthe trailer's rotational derivative, in particular the derivative of thetrailer's angle, using derivative calculation parameters comprising thedistance between the wheels of the trailer, the distance between thewheels and the hitching point, the steering angle of the front wheelsand/or the steering wheel angle, and the speed of the vehicle, and inthat the automatic panning system further is adapted to use thetrailer's angle and the calculated derivative to predict a futuretrailer angle.

According to one embodiment the automatic panning system further isadapted to identify at least one elongated element of the trailer,project a vector in the image data based on said elongated element,establish at least one reference vector, and identify an interceptionpoint of the reference vector and said projected vector.

According to one embodiment, the automatic panning system is furtheradapted to calculate an imagined cone having its center at the predictedtrailer angle of the trailer.

According to one embodiment, the automatic panning system is adapted tocalculate an imagined cone and to determine the width of the cone basedon the derivative calculation parameters.

According to one embodiment, the automatic panning system is furtheradapted to discard interception points outside the imagined cone.

According to one aspect in an automatic panning system adapted to bearranged in a vehicle with an attached trailer, wherein said automaticpanning system is configured to capture image data comprising thetrailer attached to the vehicle, the method comprises the steps:

capturing image data,

analyzing the image data to identify at least one elongated element ofthe trailer,

establishing at least one horizontal reference,

projecting a vector of the identified elongated element, and

identifying an interception point between the projected vector based onthe elongated element and the horizontal reference line.

According to one embodiment the horizontal reference is established suchthat said interception point corresponds to the position of the rear endof the trailer in the captured image data.

According to one embodiment in an automatic panning system the followingstep is performed:

panning said captured imaged data based on the interception point.

According to one embodiment the elongated element is selected from anyone of the longitudinal lower edge of the trailer, the longitudinal topedge of the trailer, the vertical rear edge of the trailer, and aprinted element on the trailer side.

According to one embodiment the horizontal reference is a horizontalreference line.

According to one embodiment the horizontal reference is determined basedon at least one distinct point in the background of the captured imagedata.

According to one embodiment the horizontal reference is a horizontalvector.

According to one embodiment the solution further comprises the steps:

determining the speed of the vehicle,

determining the processing time for capturing and analyzing image data,

determining a processing time threshold based on said speed of thevehicle,

if said threshold is exceeded, and

panning the captured image data based on vehicle sensor data.

It is one advantage with the present solution that for different travelmodes, such as different speeds, different travel directions (reverse orforward) the automatic panning system in one embodiment use differentalgorithms to pan the image. This has the effect that solution thatworks well in low speeds that at high speeds might be too slow to createa smooth experience can be combined with solution that are quick but notas accurate. Those solution presents better accuracy, for example inhigh speed travel in a forward direction relating to the vehicle'stravel direction.

According to one embodiment, the method further comprises the steps:

estimating the trailer's angle using the image capturing means andpredicting the trailer's rotational derivative, in particular thederivative of the trailer's angle, using derivative calculationparameters comprising at least one of the length of the trailer, thetrailer's hitching offset, the distance between the vehicles wheelaxles, the vehicles speed, and the steering wheel angle of the vehicle,and

using the trailer's angle and the calculated derivative to predict afuture trailer angle.

The According to one embodiment, the method further comprises the steps:

estimating the trailer's angle using the image capturing means andpredicting the trailer's rotational derivative, in particular thederivative of the trailer's angle, using derivative calculationparameters comprising the distance between the wheels of the trailer,the distance between the wheels and the hitching point, the steeringangle of the front wheels and/or the steering wheel angle, and the speedof the vehicle, and

using the trailer's angle and the calculated derivative to predict afuture trailer angle.

According to one embodiment, a method in an automatic panning systemadapted to be arranged in a vehicle with an attached trailer isprovided, wherein said automatic panning system is configured to captureimage data with a view of the trailer attached to the vehicle, themethod comprises the steps:

capturing image data,

estimating the trailer's angle using the image capturing means andpredicting the trailer's rotational derivative, in particular thederivative of the trailer's angle, using derivative calculationparameters comprising at least one of the length of the trailer, thetrailer's hitching offset, the distance between the vehicles wheelaxles, the vehicles speed, and the steering wheel angle of the vehicle,and

using the trailer's angle and the calculated derivative to predict afuture trailer angle.

According to one embodiment, a method in an automatic panning systemadapted to be arranged in a vehicle with an attached trailer isprovided, wherein said automatic panning system is configured to captureimage data with a view of the trailer attached to the vehicle, themethod comprises the steps:

capturing image data,

estimating the trailer's angle using the image capturing means andpredicting the trailer's rotational derivative, in particular thederivative of the trailer's angle, using derivative calculationparameters comprising the distance between the wheels of the trailer,the distance between the wheels and the hitching point, the steeringangle of the front wheels and/or the steering wheel angle, and the speedof the vehicle, and

using the trailer's angle and the calculated derivative to predict afuture trailer angle.

According to one embodiment, the method further comprises the steps:

analyzing the image data to identify at least one elongated element ofthe trailer,

establishing at least one horizontal reference,

projecting a vector of the identified elongated element, and

identifying an interception point between the projected vector based onthe elongated element and the horizontal reference line.

According to one embodiment, the method further comprising the steps:

calculating an imagined cone having its center at the predicted trailerangle of the trailer

According to one embodiment, the method further comprising the steps:

calculating a width of the cone determined based on the derivativecalculation parameters.

According to one embodiment, the method further comprising the steps:

discarding interception points outside the imagined cone.

BRIEF DESCRIPTION OF DRAWINGS

The invention is now described, by way of example, with reference to theaccompanying drawings, in which:

FIG. 1 illustrates an illustrative view of a trailer wherein multiplepossible vectors have been projected.

FIG. 2 illustrates one embodiment of an automatic panning system whereinan interception point between a projected vector and a reference vectorhas been detected.

FIG. 3 illustrates one embodiment of image data and panned image datawherein the panned image data is based on an identified interceptionpoint.

FIG. 4 illustrates another embodiment of image data and panned imagedata wherein the panned image data is based on an identifiedinterception point.

FIG. 5 illustrates another illustrative view of a trailer whereinmultiple possible vectors have been projected.

FIG. 6 illustrates one embodiment of image data wherein image data fromboth sides of the trailer is used for panning.

DESCRIPTION OF EMBODIMENTS

In the following, a detailed description of the different embodiments ofthe solution is disclosed under reference to the accompanying drawings.All examples herein should be seen as part of the general descriptionand are therefore possible to combine in any way of general terms.Individual features of the various embodiments and aspects may becombined or exchanged unless such combination or exchange is clearlycontradictory to the overall function of the automatic panning system.

Briefly, the solution relates to an automatic panning system forenhancing automatic panning in a rear view system of a vehicle with atrailer. The system focus on finding an interception point between aprojected vector based on an elongated element of the trailer and areference vector based on for example the horizon.

FIG. 1 shows an illustrative view of a trailer 4 adapted to be towedbehind a vehicle (not shown). The trailer comprises a number ofelongated elements 11 a, 11 b, 11 c, 11 d that is possible for an imagecapturing means such as a rear facing camera (not shown) to capture. Therear facing camera is in one embodiment arranged in the upper section ofthe height of the vehicle towing the trailer in order to capture a goodperspective for the image data with a view of the trailer 4. Theelongated elements 11 a, 11 b, 11 c, 11 d can be any form of elongatedelement such as a trailer edge. The trailer edges can be used to projecta vector in a direction enabling the system to, in combination with areference vector 21, identify how long the trailer 4 is, or where theend of the trailer 4 currently is located.

FIG. 1 further illustrates how different elongated elements 11 a, 11 b,11 c, 11 d can be used to project vectors 2 a, 2 b, 2 c, 2 d that extendoutside the perimeters of the trailer 4. The vectors 2 a, 2 b, 2 c, 2 dcan be used to determine an interception point with a reference vector21. It should further be noted that each of the vectors 2 a, 2 b, 2 c, 2d in one embodiment can be used as a reference vector 21 to identify aninterception point between the vectors.

As illustrated in FIG. 1 the trailer 4 further comprises a visible side12 a that is part of the view in the captured image data.

FIG. 2 illustrates an illustrative view of captured image data with aview of the trailer 4, here illustrated as a view of the visible side 12a. In the embodiment as illustrated in FIG. 2 a reference vector 21 hasbeen established in the image data as a horizontal reference vector 21that intersects the projected vector 2 a in the interception point 22.The interception point 22 is in the close vicinity of the position wherethe trailer ends and thereby in one embodiment provides a good point forpanning the image data in relation to.

FIG. 3 illustrates captured image data 1 in an automatic panning systemwherein a panning operation already has been conducted and the user seespanned image data 10 on for example a screen located in the driver areaof the vehicle towing the trailer 4. As can be seen in the panned imagedata 10 as illustrated in FIG. 3 the visible side 12 a of the trailer 4is located to the left and the user can see other objects 99 located inthe vicinity of the trailer 4. The projected vector 2 a, the referencevector 21, and the interception point 22 is only illustrated forillustrative purposes and is in one embodiment not shown in the pannedimage data 10. FIG. 3 further illustrates the concept of theinterception point 22 and how the panned image data 10 moves within theimage data 1 as the interception point 22 moves due to that the trailer4 turns in relation to the towing vehicle.

FIG. 4 illustrates another embodiment wherein an elongated element 11 don the trailer side has been identified instead of the lower edge of thetrailer as illustrated in FIG. 3. FIG. 4 thereby illustrates anotherembodiment wherein an interception point 22 has been identified betweena projected vector 2 d and a reference vector 21.

FIG. 5 illustrates another embodiment of the automatic panning systemwherein a trailer 4 is a lower trailer than in the previous embodiments.The illustrated trailers herein are merely examples and any form oftrailer can be used with the system. FIG. 5 thereby illustrates oneadvantage in relation to prior art that similar projected vectors 2 a, 2b, 2 c can be projected for another sort of trailer 4.

FIG. 6 illustrates another embodiment of the automatic panning systemwherein an interception point 22 is identified and a furtherinterception point 22 b at the opposite side of the trailer isidentified. The further interception point 22 b is in one embodimentanother interception point than the interception point 22. The furtherinterception point 22 b in combination with the interception point 22 isused to determine if there are any unreasonable results, such as trailermovements that wouldn't be physically possible. An example is asituation wherein the interception point 22 indicates that the traileris turning to the right and the further interception point 22 bindicates that the trailer turns to the left. In one embodiment theinterception points 22, 22 b can be seen as data points and theautomatic panning system gathers multiple data points representinginterception points 22, 22 b over time. If subsequent data pointspresent results that are not physically possible or in any other wayunreasonable the system can filter such results making the panningexperience better.

FIG. 6 further illustrates an embodiment wherein the panning system usesa further interception point 22 b to filter results that has beenaffected by disturbance, signal error, or any other form of unwantedinformation creating a faulty result. Such result can for example occurif there is interference in the system or the image data. A typicalexample can be reflections or another object visible in the image data.The solution with a further interception point 22 thereby increases theaccuracy of the algorithm used by the panning system.

Through using two sides of the trailer, i.e. the detected trailer anglefrom one side in combination with the detection of the other side theconfidence and accuracy of the readings for both sides can be enhanced.In one embodiment the accuracy can be increased further by comparingtime stamps for the data from the two sides, wherein data can bedifferent data points representing the interception point 22 and thefurther interception point 22 b.

It shall be noted that in one embodiment when the trailer moves far toone of the sides during a turn the image interception point 22 or 22 bmight not be present due to that it has moved out of the image data. Inthe same way the position of the interception point 22 and the positionof the further interception point 22 b can be compared to determine thatthe result from both sides is compatible with the result from the otherside. For example if the interception point 22 moves in a way that alarger portion of the trailer becomes visible in the captured image dataat one side, less of the trailer shall be visible on the other side.

In one embodiment a similar solution by tracking the trailer's previousangle as well as the angle of the steering wheel, alternatively thewheels, and the speed of the vehicle enables that some changes in thetrailer's angle can be excluded. In particular when going straightforward only trailer movements that bring the trailer more in line withthe vehicle shall be accepted. A more advanced implementation includespredicting the trailer's rotational derivative in particular thederivative of the trailer's angle using properties such as the length ofthe trailer, the trailer's hitching offset, the distance between thevehicles wheel axles, the vehicles speed, and the steering wheel angleof the vehicle. By estimating the trailer's angle using the imagecapturing means and a calculated derivative the future trailer angle canbe predicted. The detected angles outside a calculated cone, i.e. animagined cone extending backwards from the image capturing means, ofacceptable angles can thus be discarded.

According to one embodiment, the automatic panning system is furtheradapted to discard interception points outside the calculated cone.According to one embodiment, the automatic panning system is adapted todiscard interception points outside the calculate cone when the vectors,2 b, 2 c, 2 d are used as a reference vector 21. As a result, theautomatic panning system avoids panning captured images based onerroneous interception points generated by erroneously identifiedelongated elements or lines e.g. from shadows of the trailer captured bythe image capturing means. As an effect, the image as seen by theoperator/driver becomes less jumpy, i.e. avoiding irregular or erraticpanning movements which are irritating and less safe as the trailer mayoccasionally be outside the captured image as viewed by the operator.

According to one embodiment, the trailer angle refers to the angle ofthe trailer in relation to the cab of a vehicle.

According to one embodiment, the hitching offset is the distance betweenthe rear wheels and the hitching point of the trailer.

According to one embodiment, the calculated cone will have its center atthe predicted location, i.e. according to one embodiment, the predictedtrailer angle of the trailer. According to one embodiment, the conewidth is determined by the parameters used for its calculation.According to one embodiment, the parameters are defined by derivativecalculation parameters. According to one embodiment, the parameters aredefined by at least one of the derivative calculation parameters.According to one embodiment, the derivation calculation parameters mayin turn be calculated or determined. To determine the width of the conea deviation of the parameters can be used to calculate the longest andshortest distance the trailer might have traversed based on statisticalmodels for the deviation of parameters either individually orcollectively. According to one embodiment, the derivation calculationparameters may be predefined by being preset in the automatic panningsystem 1. According to one embodiment the end point of the cone or thewidth of the cone is defined by an elongated element or an interceptionpoint identified by the automatic panning system which deviationcompared to a previous identified elongated element or an interceptionpoint is the currently largest deviation still within a predefinedthreshold. According to one embodiment, the threshold is defining alimit for the speed of movement of the interception point. According toone embodiment, a high speed could indicate erroneous image data.

According to one embodiment, an automatic panning system adapted for avehicle with an attached trailer 4 is provided, wherein said automaticpanning system comprises an image capturing means adapted to captureimage data 1 with a view of the trailer 4, wherein the automatic panningsystem is adapted to analyze the image data 1 to estimate the trailer'sangle using the image capturing means and predict the trailer'srotational derivative, in particular the derivative of the trailer'sangle, using derivative calculation parameters comprising at least oneof the length of the trailer, the trailer's hitching offset, thedistance between the vehicles wheel axles, the vehicle's speed, and thesteering wheel angle of the vehicle, and in that the automatic panningsystem further is adapted to use the trailer's angle and the calculatedderivative to predict a future trailer angle. According to oneembodiment, the derivative calculation parameters comprising thedistance between the wheels of the trailer, the distance between thewheels and the hitching point, the steering angle of the front wheelsand/or the steering wheel angle, and the speed of the vehicle Accordingto one embodiment, the automatic panning system is adapted to analyzethe image data 1 to estimate the trailer's angle whereby estimationcomprises or is carried out by estimating the angle between the vector21, 2 b, 2 c and the reference vector 21 at the interception point 22 ofthe reference vector 21 and the vector 2 a, 2 b.

According to one embodiment, to estimate the trailer's movement, i.e. topredict the trailer rotational derivative, the distance between thewheels of the trailer, the distance between the wheels and the hitchingpoint, the steering angle of the front wheels and/or the steering wheelangle, and the speed of the vehicle are used. According to oneembodiment, further, the speed of the vehicle and angle of the wheelsare measured continuously to predict the trailer's angle. According toone embodiment, fixed distances inherent to the trailer can either beset before calculations are performed. According to one embodiment,fixed distances can be estimated using an initiation sequence where thespeed and wheel angle and/or steering wheel angle are controlled toreach a known state, such as for instance aligning the trailer with thecab wherein the trailer angle is zero, and further controlled to movethe trailer using a known speed and wheel angle and/or steering wheelangle and thus calculate the fixed distances of the vehicle using theknown speed and wheel angle and/or steering wheel angle as well as thetrailer's angle, which is identified using the image capturing means. Inparticular when the vehicle has been driving straight forward for a fewseconds the trailer's position will be known to be directly behind thevehicle. Alternatively, when the steering angle of the front wheelsand/or steering wheel angle have been kept constant during driving asufficient time in e.g. a roundabout the trailers position or angle willbe known. In a subsequent turn the steering angle and speed can bemeasured to provide an accurate calculation for the unknown parameterswheel distance and hitching offset using the measured rotation of thetrailer in said turn. This can be repeated at a later turn withdifferent speed and angles to accurately determine the previouslyunknown parameters. According to one embodiment, the calculation iscarried out with an accuracy related to the accuracy of the control ofthe speed and wheel angle and/or steering wheel angle. According to oneembodiment, the automatic panning system is adapted to analyze the imagedata 1 to estimate the trailer's angle, by or based on that theautomatic panning system being adapted to identify at least oneelongated element 11 a, 11 b, 11 c, 11 d of the trailer 4, project avector 2 a, 2 b, 2 c in the image data 1 based on said elongated element11 a, 11 b, 11 c, 11 d, establish at least one reference vector 21, andidentify an interception point 22 of the reference vector 21 and saidprojected vector 2 a, 2 b.

According to one embodiment, a risk of locking on to the wrong orerroneous line or elongated element in the image data, i.e. whenprojecting vector in the image data 1 based on a false elongated elementof the trailer or during establishing the reference vector 21 isovercome. According to one embodiment, for a moving vehicle erroneouslines or elongated elements will not persist and the automatic panningsystem is adapted to monitor the time since it last detected a line oran elongated element and release the lock of the line or the elongatedelement after a certain time such as 1 second if it no longer can detectthe lone or the elongated element. In practice this will allow thesystem to lock onto the trailer's line or elongated element efficientlywhile preventing faulty lines or elongated elements from locking downthe system completely. According to one embodiment, the system canfurther remember the trailer's position at the time of stopping toinitiate the system with greater accuracy.

1. An automatic panning system adapted for a vehicle with an attachedtrailer, wherein said automatic panning system comprises an imagecapturing means adapted to capture image data with a view of thetrailer, wherein the automatic panning system is adapted to analyze theimage data to identify at least one elongated element the trailer,project a vector in the image data based on said elongated element,establish at least one reference vector, and identify an interceptionpoint of the reference vector and said projected vector.
 2. Theautomatic panning system according to claim 1, wherein the automaticpanning system further is adapted to establish the reference vector suchthat said identified interception point corresponds to the position ofthe rear end of the trailer in the captured image data.
 3. The automaticpanning system according to claim 1, wherein said automatic panningsystem further is adapted to pan the captured image data based on theidentified interception point.
 4. The automatic panning system accordingto claim 3, wherein the automatic panning system further is adapted to,in real time, present the panned captured image data to an operator ofthe vehicle.
 5. The automatic panning system according to claim 1,wherein said identified elongated element is selected from any one ofthe longitudinal lower edge of the trailer, the longitudinal top edge ofthe trailer, the vertical rear edge of the trailer, and a printedelement on the trailer.
 6. The automatic panning system according toclaim 1, wherein the reference vector is determined based on at leastone distinct point in the background of the captured image data.
 7. Theautomatic panning system according to claim 1, wherein the referencevector is a horizontal reference vector.
 8. The automatic panning systemaccording to claim 1, wherein said automatic panning system furthercomprises a display, a memory, and a processor unit.
 9. The automaticpanning system according to claim 1, wherein the system further isadapted identify a further interception point on the opposite side ofthe trailer from the interception point, establish if the furtherinterception point is in a position that based on at least one of thephysical properties of the trailer, the previous position of thetrailer, and the interception point is possible.
 10. The automaticpanning system according to claim 1, wherein the automatic panningsystem further is adapted to calculate the vehicle speed as a functionof the velocity and angle of the wheels to predict a trailer movement.11. The automatic panning system according to claim 1, wherein theautomatic panning system is adapted to analyze the image data toestimate the trailer's angle using the image capturing means and predictthe trailer's rotational derivative, in particular the derivative of thetrailer's angle, using derivate calculation parameters comprising atleast one of the length of the trailer, the trailer's hitching offset,the distance between the vehicles wheel axles, the vehicle's speed, andthe steering wheel angle of the vehicle, and in that the automaticpanning system further is adapted to use the trailer's angle and thecalculated derivative to predict a future trailer angle.
 12. Theautomatic panning system according to claim 1, wherein the automaticpanning system is adapted to analyze the image data to estimate thetrailer's angle using the image capturing means and predict thetrailer's rotational derivative, in particular the derivative of thetrailer's angle, using derivative calculation parameters comprising thedistance between the wheels of the trailer, the distance between thewheels and the hitching point, the steering angle of the front wheelsand/or the steering wheel angle, and the speed of the vehicle, and inthat the automatic panning system further is adapted to use thetrailer's angle and the calculated derivative to predict a futuretrailer angle.
 13. (canceled)
 14. (canceled)
 15. (canceled)
 16. Theautomatic panning system according to claim 11, wherein the automaticpanning system is further adapted to calculate an imagined cone havingits center at the predicted trailer angle of the trailer.
 17. Theautomatic panning system according to claim 16, wherein the automaticpanning system is further adapted to discard interception points outsidethe imagined cone.
 18. Method in an automatic panning system adapted tobe arranged in a vehicle with an attached trailer, wherein saidautomatic panning system is configured to capture image data with a viewof the trailer attached to the vehicle, the method comprises the steps:capturing image data, analyzing the image data to identify at least oneelongated element of the trailer, establishing at least one horizontalreference, projecting a vector of the identified elongated element, andidentifying an interception point between the projected vector based onthe elongated element and the horizontal reference line.
 19. The methodaccording to claim 18, wherein the horizontal reference is establishedsuch that said interception point corresponds to the position of therear end of the trailer in the captured image data.
 20. The methodaccording to claim 18, wherein the method further comprises the step:panning said captured imaged data based on the interception point. 21.The method according to claim 18, wherein said identified elongatedelement is selected from any one of the longitudinal lower edge of thetrailer, the longitudinal top edge of the trailer, the vertical rearedge of the trailer, and a printed element on the trailer.
 22. Themethod according to claim 18, wherein said reference vector is ahorizontal reference vector.
 23. The method according to claim 18,wherein the horizontal reference is determined based on at least onedistinct point in the background of the captured image data.
 24. Themethod according to claim 18, wherein the method further comprises thesteps: determining the speed of the vehicle, determining the processingtime for the steps according to claim 18, determining a processing timethreshold based on said speed of the vehicle, if said threshold isexceeded, and panning the captured image data based on vehicle sensordata.
 25. The method according to claim 18, the method further comprisesthe steps: estimating the trailer's angle using the image capturingmeans and predicting the trailer's rotational derivative, in particularthe derivative of the trailer's angle, using derivative calculationparameters comprising at least one of the length of the trailer, thetrailer's hitching offset, the distance between the vehicles wheelaxles, the vehicles speed, and the steering wheel angle of the vehicle,and using the trailer's angle and the calculated derivative to predict afuture trailer angle.
 26. The method according to claim 18, the methodfurther comprises the steps: estimating the trailer's angle using theimage capturing means and predicting the trailer's rotationalderivative, in particular the derivative of the trailer's angle, usingderivative calculation parameters comprising the distance between thewheels of the trailer, the distance between the wheels and the hitchingpoint, the steering angle of the front wheels and/or the steering wheelangle, and the speed of the vehicle, and using the trailer's angle andthe calculated derivative to predict a future trailer angle. 27.-31.(canceled)